Direct Evidence That Polysorbate-80-Coated Poly(Butylcyanoacrylate) Nanoparticles Deliver Drugs to the CNS via Specific Mechanisms Requiring Prior Binding of Drug to the Nanoparticles

Purpose. It has recently been suggested that the poly(butylcyanoacrylate) (PBCA) nanoparticle drug delivery system has a generalized toxic effect on the blood-brain barrier (BBB) (8) and that this effect forms the basis of an apparent enhanced drug delivery to the brain. The purpose of this study is to explore more fully the mechanism by which PBCA nanoparticles can deliver drugs to the brain. Methods. Both in vivo and in vitro methods have been applied to examine the possible toxic effects of PBCA nanoparticles and polysorbate-80 on cerebral endothelial cells. Human, bovine, and rat models have been used in this study. Results. In bovine primary cerebral endothelial cells, nontoxic levels of PBCA particles and polysorbate-80 did not increase paracellular transport of sucrose and inulin in the monolayers. Electron microscopic studies confirm cell viability. In vivo studies using the antinociceptive opioid peptide dalargin showed that both empty PBCA nanoparticles and polysorbate-80 did not allow dalargin to enter the brain in quantities sufficient to cause antinociception. Only dalargin preadsorbed to PBCA nanoparticles was able to induce an antinociceptive effect in the animals. Conclusion. At concentrations of PBCA nanoparticles and polysorbate-80 that achieve significant drug delivery to the brain, there is little in vivo or in vitro evidence to suggest that a generalized toxic effect on the BBB is the primary mechanism for drug delivery to the brain. The fact that dalargin has to be preadsorbed onto nanoparticles before it is effective in inducing antinociception suggests specific mechanisms of delivery to the CNS rather than a simple disruption of the BBB allowing a diffusional drug entry.     

Alpha4-integrin-VCAM-1 binding mediates G protein-independent capture of encephalitogenic T cell blasts to CNS white matter microvessels

Direct in vivo evidence is still lacking for alpha4-integrin-mediated T cell interaction with VCAM-1 on blood-brain barrier-endothelium in experimental autoimmune encephalomyelitis (EAE). To investigate a possible alpha4-integrin-mediated interaction of encephalitogenic T cell blasts with VCAM-1 on the blood-brain barrier white matter endothelium in vivo, we have developed a novel spinal cord window preparation that enabled us to directly visualize CNS white matter microcirculation by intravital fluorescence videomicroscopy. Our study provides the first in vivo evidence that encephalitogenic T cell blasts interact with the spinal cord white matter microvasculature without rolling and that alpha4-integrin mediates the G protein-independent capture and subsequently the G protein-dependent adhesion strengthening of T cell blasts to microvascular VCAM-1.     

Amelioration of immune-mediated experimental colitis: tolerance induction in the presence of preexisting immunity and surrogate antigen bystander effect

Oral tolerance is a recognized procedure for induction of antigen-specific peripheral immune hyporesponsiveness. Recently, it has been shown that oral tolerance can be used to prevent experimental colitis. The aim of this study was to test whether induction of oral tolerance toward proteins extracted from inflammatory and noninflammatory colons can alleviate preexisting experimental colitis. Colitis was induced in BALB/c mice by intracolonic instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS). Mice received five oral doses of colonic proteins extracted from TNBS-induced colitis or normal colons, before, or 7 days after colitis was induced. Standard clinical, macroscopic, and microscopic scores were used for colitis assessment. Serum interferon gamma (IFNgamma) and interleukin (IL)4 levels were measured by enzyme-linked immunosorbent assay. Feeding of colitis- or normal colon-extracted proteins before, or following colitis induction, ameliorated colonic inflammation as shown by decreased diarrhea, increased body weight, reduction of colonic ulcerations, intestinal and peritoneal adhesions, wall thickness, and edema. Histological parameters for colitis were markedly improved in tolerized animals, and there was a significant reduction in inflammatory response and mucosal ulcerations. Tolerized mice developed an increase in IL4 and a decrease in IFNgamma serum levels. The results show that induction of oral tolerance to colitis- or normal colon-extracted proteins down-regulated preexisting anticolon immune response, thereby ameliorating experimental colitis. Tolerance induction was mediated via a shift from a proinflammatory T helper (Th)1 to an anti-inflammatory Th2 immune response.     

Acupuncture in the treatment of psychogenic erectile dysfunction: first results of a prospective randomized placebo-controlled study

In a prospective study, we investigated the potentially curative effect of acupuncture in patients with psychogenic erectile dysfunction (pED). A total of 22 patients with pED were randomized into two groups. They were either treated with acupuncture specific against ED (treatment group) or acupuncture specific against headache (placebo group). Nonresponders of the placebo group were crossed over to the treatment group. Prior to acupuncture, serum sexual hormone levels, IIEF score, nocturnal penile tumescence testing for three nights (Rigiscan) and the erectile response to 50 mg sildenafil were evaluated. Out of 21 patients, 20 completed the study, including 10 patients after crossover. A satisfactory response was achieved in 68.4% of the treatment group and in 9% of the placebo group (P=0.0017). Another 21.05% of the patients had improved erections, that is, sufficient rigidity under simultaneous treatment with 50 gm sildenafil. The results of our pilot study indicate that acupuncture can be an effective treatment option in more than two-thirds of patients with psychogenic erectile dysfunction.     

Urinary uranium concentrations in an enlarged Gulf War veteran cohort

Depleted uranium was first used on a large scale as a major component of munitions and armaments employed by the U.S. armed forces during the Gulf War in 1991. In response to concern that exposure to depleted uranium may have been a cause of health problems suffered by returning veterans of that war, an already existing surveillance program following depleted uranium "friendly fire" victims was enlarged to assess the wider veteran community's exposure to depleted uranium. Between August 1998 and December 1999, 169 Gulf War veterans submitted 24-h urine samples for determination of urinary uranium concentration and questionnaires describing their potential exposures to depleted uranium while in the Gulf War theatre. Depleted uranium exposure assessment was determined from 30 separate questionnaire items condensed into 19 distinct exposure scenarios. Results of urine uranium analysis were stratified into high and low uranium groups with 0.05 microg uranium/g creatinine being the cut point and approximate upper limit of the normal population distribution. Twelve individuals (7.1%) exhibited urine uranium values in the high range, while the remaining 157 had urine uranium values in the low range. A repeat test of urine for 6 of these 12 produced uranium results in the low range for 3 of these individuals. Exposure scenarios of the high and low uranium groups were similar with the presence of retained shrapnel being the only scenario predictive of a high urine uranium value. Results emphasize the unlikely occurrence of an elevated urine uranium result and consequently any uranium-related health effects in the absence of retained depleted uranium metal fragments in the veterans.     

Biomorphometry of corneal epithelium with slit lamp-adapted optical coherence tomography

Introduction. The purpose of this study was to evaluate the biomorphometry of the corneal epithelium with slitlamp-adapted optical coherence tomography (OCT). Patients and methods. In a clinical study, slitlamp-adapted OCT of the cornea was performed in 15 patients before and immediately after therapeutic corneal abrasion. Central corneal epithelium thickness measurements were compared to the pre- and postoperative central corneal thickness. Results. Preoperatively, the corneal epithelium could be visualised from the highest OCT light reflections at the interfaces air-tear film and epithelium-Bowman's membrane. The preoperative mean geometrical central epithelial thickness determined with OCT ranged from 65±12 μm to 72±14 μm (45–92 μm). The mean difference of the pre-and postoperative central corneal thickness was 48±19 μm (9–79 μm). This resulted in a deviation from the direct epithelial thickness measurements of 26–33%. The reproducibility of the geometrical epithelial thickness was ±9 μm. Conclusions. Slitlamp-adapted OCT enabled a noncontact evaluation of the corneal epithelium. The difference between direct and indirect corneal epithelium thickness measurements could be related to the partial optical inclusion of the precorneal tear film and the Bowman's membrane. With some restrictions the biomorphometry of the corneal epithelium with slitlamp-adapted OCT seems to be a valuable technique to monitor therapeutical and refractive procedures of the cornea.     

Abolition of (-)-CGP 12177-evoked cardiostimulation in double β1/β2-adrenoceptor knockout mice. Obligatory role of β1-adrenoceptors for putative β4-adrenoceptor pharmacology

Some beta1- and beta2-adrenoceptor-blocking agents, such as (-)-CGP 12177, cause cardiostimulant effects at concentrations considerably higher than those that antagonise the effects of catecholamines. The cardiostimulant effects of these non-conventional partial agonists are relatively resistant to blockade by (-)-propranolol and have been proposed to be mediated through putative beta4-adrenoceptors or through atypical states of either beta1- or beta2-adrenoceptors. We investigated the effects of (-)-CGP 12177 on sinoatrial rate and left atrial contractile force as well as the ventricular binding of (-)-[3H]CGP 12177 in tissues from wild-type, beta2-adrenoceptor knockout and beta1/beta2-adrenoceptor double knockout mice. The cardiostimulant effects of (-)-CGP 12177 were present in wild-type and beta2-adrenoceptor knockout mice but were absent in beta1/beta2-adrenoceptor double knockout mice. Thus, the presence of beta1-adrenoceptors is obligatory for the cardiostimulant effects of (-)-CGP 12177. It appears therefore that an atypical state of the beta1-adrenoceptor contributes to the mediation of the cardiostimulant effects induced by non-conventional partial agonists. Ventricular beta1- and beta2-adrenoceptors, labelled in wild-type with a K(D) approximately 0.5 nmol/l (approximately 16 fmol/mg protein), were absent in beta1/beta2-adrenoceptor double knockout mice. However, a high density binding site (approximately 154-391 fmol/mg protein) that did not saturate completely (K(D) approximately 80-200 nM) was labelled by (-)-[3H]CGP 12177 in the three groups of mice, being distinct from beta1- and beta2-adrenoceptors, as well as from the site mediating the agonist effects of (-)-CGP 12177.     

Recruitment of activated microglia cells in the spinal cord of mice by ALS IgG

Mice were injected i.p. with IgG samples of different patients to test whether IgG from amyotrophic lateral sclerosis (ALS) can initiate an immune/inflammatory reaction targeting motor neurons. All IgG samples of five ALS patients and none of the disease controls recruited activated microglia cells in the ventral horn of the spinal cord. CD3 lymphocytes were not accumulated in the same tissue. Similar reaction was evoked by injection of IgG from guinea pigs with experimental autoimmune gray matter disease (EAGMD) induced by immunization with the homogenate of the ventral horn of bovine spinal cord. The results indicate that ALS IgG and anti-motoneuron IgG induce microglia reaction targeting motor neurons without initiating T cell response in the recipient mice.     

Necrotizing fasciitis as complication of injection into greater trochanteric bursa

Necrotizing fasciitis is a limb- and life-threatening soft-tissue infection that frequently involves the extremities. This article describes the first case of necrotizing fasciitis developing from a single steroid injection of the greater trochanteric bursa. Despite early resuscitation and aggressive surgical management that included a hip disarticulation, the patient expired. Potential contributing factors are reviewed.